<meta name="viewport" content="width=device-width; initial-scale=1.0">
<style type="text/css">
a {
 display:block;
 background: #333;
 border-radius: 10px;
 color: #FFF;
 margin: 20px;
 padding: 5px 8px;
 text-align: center;
 text-decoration: none;
}
</style>
<a href="#">Demo</a>
<script type="text/javascript">
 var button = document.querySelector('a');
 button.addEventListener( 'click', function(e){
	e.preventDefault();
	native_interface.showToast("Hello from JavaScript");
 });

 function setButtonLabel(label){
	button.innerText = label;
 }

</script>
